1. Field of the Invention
The present invention relates to sheet metal construction, and more particularly, to a unique sheet metal construction system in which sheet metal is secured to a support strut with a rivet that is received within an elongated channel formed in the support strut. The strut is also provided with channels for receiving fasteners or other devices such as braces and hangers for suspending a finished sheet metal product, such as a plenum for a clean room.
2. Description of Related Art
Sheet metal is a strong, lightweight material that is ideally suited for many types of construction. However, in some situations, sheet metal alone may not be strong enough to be self-supporting. For this reason, in many types of sheet metal construction, a sheet metal "skin" is secured over a frame of supporting struts. In this manner, the sheet metal provides a lightweight and easily contoured surface and the frame provides the necessary structural stability.
In such systems, the sheet metal can be attached to the frame by a variety of methods. For example, fasteners, such as metal screws, bolts, or rivets, can be used to fasten the sheet metal to the frame. Typically, the use of such fasteners requires that a hole be drilled or punched in the sheet metal and a corresponding hole be drilled or punched into the frame. The two holes are then aligned and the fastener is inserted into the hole to attach the sheet metal to the frame.
Although this type of construction is durable and strong, it can greatly complicate the construction process. For example, if the holes in the sheet metal and the frame are pre-punched or drilled, extremely tight tolerances must be maintained. Otherwise, the holes may not line up when the sheet metal is placed over the frame and it will be impossible to insert the fastener. Alternatively, the sheet metal can be placed over the frame and the holes drilled in place. This technique, however, may be labor intensive and slow. It also creates metal particles and filings that can contaminate the finished product. Such contamination is unacceptable in the construction of many sheet metal items, such as a plenum for a clean room.